Scaffold.



W. 0. FRITZ.

SGAFFOLIL.

APPLICATION FILED NOV.'8, 1911.

1,033,389. Patented July 23, 1912.

WILLIAM C. FRITZ, OF CHICAGO, ILLINOIS.

SCAFFOLD.

Specification of Letters Patent.

Application filed. November 8, 1911.

Patented July 23, 1912.

Serial No. 659,088.

- To all whom it may concern.

Be it known that I, IVILLIAM C. FRITZ, a citizen of the United States,and residing at Chicago, in the county of Cook and 3 State of Illinois,have invented a new and useful Improvement in Scaffolds, of which thefollowing is a complete specification.

The main objects of this invention are to provide an improved scaffold;to provide a scaffold adapted to be adjusted as to length and as toheight; to provide novel mechanism for supporting and adjusting thescaffold vertically; and to provide a strong and durable constructionadapted to be folded into small compass when not in use.

The invention consists of the matters hereinafter described and morefully pointed out and defined in the appended claim.

In the drawings: Figure 1 is a fragmentary perspective view of ascaffold embodied in this invention with the extension legs at one endshown in dotted lines in position to be adjusted and also extended. Fig.2 is a fragmentary side elevation of the scaffold in folded position.Fig. 3 is an end elevation of the scafiold. Fig. 4 is a fragmentary,side elevation of a modified form of the scaffold. Fig. 5 is a sideelevation of one of the cross bars for the inner legs of theconstruction shown in Fig. 1.

As shown in the drawings: Referring first to Figs. 1 to 3 inclusive, thescaffold is provided with a longitudinally extensible platform,comprising a central section 1 and end sections 2 and 3. Each sectioncomprises side members or stringers 1 which taper from their under edgesupwardly toward their ends, and on which are cross boards 5. The centralsection 1 is provided with transverse cleats 6 extending across thebottom thereof, and the end sections, which are narrow enough to slidebetween the stringers of the central section, are slidably mounted attheir inner ends on said cleats, and are provided on their inner endswith transverse cleats 7, adapted when fully extended to abut againstthe cleats 6 and prevent the end sections from being withdrawn from thecentral section. Any desired means may be employed to hold the endsections in adjusted position. The central section 1 is provided on eachend with a metal reinforcing band 8 which is bent down at its ends tooverlap the stringers, and is secured thereto.

The main legs 9 are pivoted at their upper ends to the end sections 2and 3, near the outer ends thereof, by. means of rods 10. Connecting thetwo legs at each end of the scaffold are cross bars 11 which are spaceda distance apart, and the outer ends of which are flush with the outersides of the legs. The lower ends of said legs are wider than theremaining portion to provide feet 12 adapted to give greater stabilityto the structure.

Slidably mounted on the outer sides of the legs 9 are the extension legs13, which are also connected together by cross bars 14 adapted toalternate with the cross bars 11, so that one bears or rests on theother. The legs 13 are provided at their upper ends, above the uppercross piece let, with hooks 15 which hook around the front edges of thelegs 9 and prevent the upper ends of the legs 13 from tipping outwardly.

Braces 16 are pivoted at their rear ends to the inner sides of the legs9 and extend upwardly and inwardly and are hooked to pins 17 on thesides of the sections 2 and 3. A bar 18 is pivoted to each brace 16 andextends toward the legs and is adapted to hook onto a pin 19 on theinner side of the leg 9. The bars 18 provide steps to be used whenmounting the scaffold. The legs 9 and 13 are provided with registeringapertures 20 adapted to receive plns to hold the legs in properrelation.

In the construction shown in Figs. 1, 2 and 3, the scaffold is adaptedto be raised above the height of the legs 9. In the construct-ion shownin Fig. 4 the platforms are adapted to be lowered on the legs 9. In thislatter construction the legs 13 are connected together by cross bars 21,which are of less width than the bars 14:, and are provided with notches22 in which notches 23 in the stringers of the end section engage, andthe legs 9 are connected together by bars 241 on which the bars 21 rest.

The operation is as follows: In the construction shown in Figs. 1, 2 and3, the platforms may be extended longitudinally by adjusting the endsections in the central section. When it is desired to raise theplatform to a greater height than that afforded by the legs 9, the lowerends of the legs 13 are swung outwardly, as shown in dotted lines inFig. 1, until the bars 14: clear the bars 11. The outer legs 13 may thenbe moved downwardly and swung back to place to permit the bars 11 torest on the bars 1 1. When the scaffold is not in use the legs may befolded under the platform as shown in Fig. 2.

In the construction shown in Fig. 4 the platform may be supported on anyof the bars 21.

Obviously many details of the constructions shown may be varied oromitted without departing from the scope of the claim.

I claim:

A'sca'ttold comprising an extensible platform, main legs hinged to theplatform extension legs slidably mounted on said main legs, cross barsconnecting each pair of main legs together, and each pair of extensionlegs together, the cross bars of the main legs being adapted to besuperimposed on the cross bars of the extension legs, retaining hooks onthe extension legs adapted to allow the lower portions to swing out foradjustment, and braces on the main legs removably connected to theplatform, sub stantially as set forth.

In testimony whereof I have hereunto subscribed my name in the presenceof two witnesses.

WILLIAM C. FRITZ.

Vitnesses JOSEPH SCHLENKER, R0131". KLoTz.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of latents,

Washington, D. C.

